Software as a service (SaaS), is a model of cloud computing in which applications (software) are hosted by a vendor and provided to the user as a service. SaaS applications are licensed on a subscription basis and are made available to users over a network, typically the internet.
Because SaaS applications can be accessed at any time, at any place, and on any platform, they have become a popular model for the delivery of many business applications. A well-known example of SaaS is Microsoft’s Office 365, which provides Microsoft’s famous suite of productivity software— including MS Word and Excel— as a service.
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